Bituminous road pavement



y 1944- H. s. eooowm 2,353,027

BITUMINOUS ROAD PAVEMENTS Filed May 3, 1940 CYOSS Sec'hona'l Mw ofRoacl (lonsfruc'h ou Emp'lnyi-nq 'Fr'eated. Cefion Fabric.

a Surface or Wearing C urse I) Asphalt Weafec] Graded Aggr-cgatawa C- Weaied Fa brie.

. a- Fri med Su'b-graJe b Z'WSGWSWVM J3 W a 4 Patented July 4, 1944 2,353,027 BITUMINOUS noAn PAVEMENT Henry S. Goodwin, East Bound Brook, N. J., as- I signor to Standard Oil Development Company, a corporation of Delaware Application May 3, 1940, Serial No. 383,156

Claims.

This invention relates to improvements in bituminous road pavements and particularly in the method of laying bituminous road pavements.

In laying bituminous road pavements, the use of cotton fabric is gradually increasing, especially in pavements that are subjected to very heavy traflic where the cotton acts as a binding and shock-absorbing agent. These pavements also are adapted to be used as linings in canals, both for the bottoms of the canals and also the sides. A disadvantage found in the use of cotton fabric and, in fact, in the use of other fibrous material is that the fabric absorbs some of the moisture from the base with the result that the adhesivity of the fabric and the bituminous material is materially reduced. The bituminous material tends to part from the fabric and also the fabric tends to stretch and/or weaken due to rotting. Attempts have been made to overcome these difliculties by waterproofing this fabric by saturating with a bituminous composition such as a good grade of soft blown asphalt with or without first pretreating with a bituminous saturating compound. Even then the treated fabric and the top surface bituminous composition does at times tend to part.

An object of this invention is to overcome the above-mentioned difiiculties currently encountered from the use of cotton cloth in pavements by the use of a fabric which has been made water repellant by impregnation with aluminum stearate.

Another object of this invention is to provide a pavement which possesses a greater adhesion of the ingredients in the pavement with a certainmeasure of vibration-absorbing property.

Still another object of this invention is to provide a pavement in which the bond between a fibrous fabric used in the pavement and the bituminous composition is greatly improved.

A further object of this invention is to provide a pavement that will withstand weathering, such as rain, frost and snow, over prolonged periods of time.

According to this invention, cotton fabric or other fibrous material that is to be used in the construction of pavements, ,may be prepared in any manner which will leave the fibers of the material sufliciently impregnated with aluminum stearate to render them substantially waterproof. One known method by which this is accomplished is to first saturate the cloth or fibrous material withan aqueous solution of aluminum acetate of about 4 to 5 Baum gravity, then to pass the aqueous solution of a water-soluble stearate soap,

such as sodium stearate, to precipitate aluminumtion is at times used as a fixing agent, through which the fabric is passed just after the preeipitation of the aluminum stearate, and prior to the final washing or rinsing step.

The aluminum stearate impregnated fabric is then laid on the surface of a road or canal base that has previously been prepared. If desired, the base may be primed with a flux oil or cutback liquid asphalt preparation and allowed to cure for about a day before the. addition of the fibrous fabric. Fine, medium, or coarse mesh fabrics may be used.

The fabric may be treated with an asphalt cutback oil, and sand spread on top. Another method is to cover fibrous fabric material with a good coating of asphalt and cut stone which is then rolled and finally given a top coat of asphalt.

When used in lining canals, the base is generally given a prime coat of road oil and a coating naphthenate, lead sulfonate, or free fatty acids,

may likewise be incorporated in the flux or asphaltic material that is used.

These bituminous road pavements are especially useful wherever extensive areas are required to be paved and maintained smooth, such as airplane port fields,'kennel'fioors and runs, driveways, garage floors, tennis courts. etc.

I claim:

1. A pavementcomprising as a supporting sub structure a fibrous material which has been previously impregnated with a metallic stearat'and a top wearing surface of bituminous material.

2. A pavement comprising a bituminous oil treated substructure, a fibrous material which has saturated material into a bath containing an been previously impregnated with aluminum with anasphalt composition.

4. A method of laying a pavement which comprises preparing a substructure, treating it with an asphaltic mineral oil, laying on the asphaltictreated substructure the asphalt coated fabric previously impregnated with aluminum stearate, and covering the coated fabric with a mixture of mineral aggregate and bituminous material.

5. A method of laying a pavement according to claim 4 in which the bituminous material used. in bonding the mineral aggregate contains: a wetting agent.

6. A method of laying a pavement which comprises coating, a substructure with an asphaltic flux oil, laying onv the substructure a cotton fabric that had been impregnated with aluminum stearate and covering the cotton fabric with a mixture of mineral aggregate, powdered asphalt and flux oil, and compacting the mixture cold by the application of pressure.

7. A method of laying a pavement according to claim 6 in which the cotton fabric is impreghated with aluminum stearate by saturating the cotton fabric with a water solution of an aluminum salt and then passing the aluminum salt treated fabric through a bath containing an aqueous solution of sodium stearate, after which the fabric is dried.

8. A method of laying a pavement which comprises saturating a fibrousmaterial with a water solution of an aluminum salt and then passing the aluminum salt treated fabric through a bath containing an aqueous solution of sodium stearate, pressing to remove most, of the liquids, drying the fabric, coating a. substructure with an asphalt flux oil, laying on the asphaltic. flux oil treated substructure the aluminum salt treated dry fabric, coating the aluminum salt treated dry fabric with a mixture of, mineral aggregate, powdered asphalt and flux oil, and compacting the.

, then passing the aluminum salt treated fabric 

